Field of the Invention
The present invention relates to methods of building stereoscopic models and, more particularly, to a method of building a stereoscopic model with Kalman filtering that corrects errors and enhances accuracy.
Description of the Prior Art
Human beings, objects, and spaces are visualized mainly by 2D pictures displayed on a conventional network or application. Surfers watch a human being, an object, and a space from different angles or in different directions by browsing multiple 2D pictures taken of the human being, the object, and the space from different angles. The prior art has drawbacks as follows: a lack of stereoscopicity and directivity; the surfers have to browse, one by one, multiple 2D pictures taken from different angles; the 2D pictures do not enable the surfers to intuitively choose to browse the images of the human being, the object, and the space from a specific angle; and, when browsing a 2D picture, the surfers have to imagine or judge the angle from which the 2D picture was taken of the human being, the object, or the space. For example, a physician providing a long-distance medical service to a patient can watch the patient's face by long distance photography, only if the physician and the patient are online simultaneously; however, the physician is unable to manipulate and choose whatever angles of view but has to instruct the patient to rotate his or her head. Alternatively, if the physician and the patient are not online simultaneously, the patient may take pictures of himself or herself and then send the pictures to the system end for the physician to browse; however, the physician can only browse the pictures one by one rather than watch the patient's on the spot and with stereoscopicity.
To achieve stereoscopicity, the prior art discloses building a 3D model of a human being or an object with stereoscopic imaging techniques, such as feature-point based recognition and trigonometry. However, 3D stereoscopic space stereoscopic imaging requires special instruments, entails building a model of a “specific subject”, incurs high costs, takes much time, and is predisposed to distortion. Conventional panoramas, Google Street View, and Photo Tourism allow users to access a view from a fixed reference point rather than provide an omnidirectional view of a specific subject.
Panoramas, which are created by joining multiple pictures, are good at processing simple spatial relationships but poor in visualizing a single object. Google Street View requires special equipment for capturing images and spatial information to construct a spatial correlation between images. Photo Tourism (Photo synth) creates an image space by a 3D stereoscopic model building process and searches for pictures according to relative positions of feature points.
Taiwan patent 1476729, entitled “Method and system for integrating 2D picture and 3D model, and computer program product of the same”, discloses: a corresponding relationship between a 3D stereoscopic model and a 2D picture is constructed; the system provides an operating interface; functions provided by the operating interface comprise specifying a feature point on the 2D picture and configuring a confirmation point on the 3D stereoscopic model, wherein the confirmation point corresponds to the feature point; a display space vector of the 2D picture is determined according to a viewing angle space vector of the 3D stereoscopic model; and a 2D picture corresponding to a display space vector is selected and displayed as soon as the operating interface displays the 3D stereoscopic model according to a specific viewing angle space vector. However, Taiwan patent 1476729 has a drawback, that is, during a process of building a 3D stereoscopic model, increased system variation, increased complexity, or increased coverage, for example, in the situation where objects are moving, tends to cause system misreading and accuracy deterioration, thereby leading to the distortion of the 3D stereoscopic model thus built.